FIG. 18 is a cross-sectional view of a thermoelectric converter useful in a refrigerator or the like. A group of thermoelectric elements 103 is arranged on an outer surface of a metallic container made of aluminum with an aluminum-made, blocked heat-absorbing-side thermal conductor 102 interposed therebetween, and a heat-dissipating-side thermal conductor 105 provided with heat-dissipating fins 104 is disposed on an outer side of the group of thermoelectric elements 103.
A heat-insulating layer 106 is interposed between the metallic container 101 and the heat-dissipating-side thermal conductor 105 such that the blocked heat-absorbing-side thermal conductor 102 and the thermoelectric element group 103 are surrounded by the heat-insulating layer. Although not illustrated in the drawing, the heat-insulating layer 106 is composed of a frame member, which is formed of a molded body of a synthetic resin, and a heat-insulating material filled inside the frame member and made of a foamed resin such as polyurethane.
In the above-described construction, accurate dimensions can hardly be achieved due to molding strains or the like because the frame member defining the contour of the heat-insulating layer 106 is formed of the molded body of the synthetic resin. Further, the thickness of the heat-insulating layer 106 tends to become greater than a predetermined dimension due to an expansion which in turn takes place as a result of foaming of the heat-insulating material.
In general, the metallic container 101 and the heat-absorbing-side thermal conductor 102 are connected together by bolts or the like, and the thermoelectric element group 103 is attached to the heat-dissipating-side thermal conductor 105. Due to the interposition of the heat-insulating layer 106 between the metallic container 101 and the heat-dissipating-side thermal conductor 105, the close contact between the heat-absorbing-side thermal conductor 102 and the thermoelectric element group 103 tends to deteriorate due to the above-mentioned dimensional scatters and expansions. This results in a higher thermal resistance, thereby developing a problem that the thermoelectric conversion characteristics are lowered.
An object of the present invention is to solve such drawbacks of the conventional art and to provide a thermoelectric converter excellent in performance.